6:30pm is way too early to raise a complaint about noise unless it's constantly happening and causing significant disruption.
Having said this, this guy sounds like a proper twunt and could do with being a bit more considerate to you (and everyone else around him).
Selfish disruptive neighbours cause people a great deal of stress and the situation ain't funny when you are on the receiving end!
My advice is approach them when you have calmed down and try to agree a compromise (but don't expect a great deal as types like this usually don't have a capacity for empathy, or are just plain selfish). You can but try.
Good luck with the baby! My experience is that it takes forever to get them to sleep, with the tiniest noise waking them up, however, once they are off, you could make as much noise as you like and they still won't stir. Could never work that one out. The baby phase is a short one thankfully!